From mboxrd@z Thu Jan  1 00:00:00 1970
From: linux@arm.linux.org.uk (Russell King - ARM Linux)
Date: Mon, 4 Jan 2010 11:11:37 +0000
Subject: [PATCH 4/5] arm: enable support for software perf events
In-Reply-To: <1262602122-10373-5-git-send-email-jamie.iles@picochip.com>
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Message-ID: <20100104111137.GC9107@n2100.arm.linux.org.uk>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On Mon, Jan 04, 2010 at 10:48:41AM +0000, Jamie Iles wrote:
> +/* Get the PC. Make sure that we have a 64bit value with the upper 32 cleared.
> + */
> +#define perf_instruction_pointer(_regs) \
> +	((u64)instruction_pointer(regs) & 0xFFFFFFFFLU)

Maybe we should make pt_regs entries be unsigned instead of having this?
Nothing should be affected by that change - and it looks like x86 went
through this change, making two pt_regs structures, one for userspace
with signed ints/longs, and one for kernel space with unsigned ints/longs.

I think it would make more sense to do that rather than litter the kernel
with casts like the above.